The present invention generally relates to an image processing apparatus such as a facsimile device or the like, and more particularly to an image processing apparatus that uses expendables to print an image.
A recent facsimile device employs a printing unit of an electrophotographic type. This printing unit performs printing by forming an electrostatic latent image on a photosensitive drum, developing the latent image into a toner image with toner deposited on the photosensitive drum and selectively adhered to the latent image, and transferring the toner image to plain paper. The toner and the photosensitive drum are expendables that are decreased or deteriorated by repetitive printing. Consequently, the facsimile device monitors the consumed amount of toner and the number of times the photosensitive drum is used for printing, and issues a request for maintenance such as supplement of the toner or replacement of the photosensitive drum to the user by a display or the like when it is determined that the remaining amount of toner is low or the remaining service life of the drum is short.
Generally, a request to the user is issued early enough to allow a time margin for procurement of the expendables, i.e., toner and photosensitive drum. Even after issuance of the request, the printing unit is able to continue normal printing for a while. If the toner is supplemented before the complete depletion thereof and the photosensitive drum is replaced before the complete wear-out thereof, the situation can be avoided in which the printing unit is unusable due to the matter of the expendables.
Incidentally, the expendables must be obtained by a request to a supplier such as a sales dealer, or a visit to the supplier. In some cases, the expendables are sold out and not available within the time margin for procurement. In preparation for such cases, a number of such expendables are purchased at one time and stocked close at hand so that they can be ready for use. However, it is time-consuming to carry out continuous stock management for preventing the expendables from being out of stock.